title: Estimation of the size of the alloreactive NK cell repertoire: studies in individuals homozygous for the group A KIR haplotype.
abstract: Stem cell transplantation across HLA barriers may trigger NK cell-mediated graft-vs-leukemia effects leading to improved survival for patients with hematological malignancies. However, the genetic algorithm based on killer cell Ig-like receptor (KIR) and HLA genes used to predict NK cell alloreactivity have yielded discrepant results. Accordingly, it has been difficult to define transplantation settings that favor NK cell alloreactivity. In this study, we have used multiparameter flow cytometry to simultaneously analyze the cell surface expression of all four major inhibitory KIR and CD94/NKG2A to determine the size of the alloreactive NK cell repertoires in 31 individuals homozygous for the group A KIR haplotype. We observed a vast variability in the frequencies of cells with an alloreactive potential, ranging from 0 to 62% of the total NK cell population depending on which, and how many, KIR ligands were missing in theoretical recipients. This analysis required a functional examination of KIR3DL2-single positive NK cells, showing that this subset was hyporesponsive in individuals harboring the cognate ligands HLA-A3/A11. The results provide new insights into the variability of the functional alloreactive NK cell repertoire and have implications for donor selection in hematopoietic stem cell transplantation and adoptive NK cell-based immunotherapy.
authors.affiliation: Center for Infectious Medicine, Department of Medicine, Karolinska Institutet, Karolinska University Hospital, Stockholm, Sweden.
authors.forename: Cyril
authors.initials: C
authors.lastname: Fauriat
authors.forename: Sandra
authors.initials: S
authors.lastname: Andersson
authors.forename: Andreas T
authors.initials: AT
authors.lastname: Björklund
authors.forename: Mattias
authors.initials: M
authors.lastname: Carlsten
authors.forename: Marie
authors.initials: M
authors.lastname: Schaffer
authors.forename: Niklas K
authors.initials: NK
authors.lastname: Björkström
authors.forename: Bettina C
authors.initials: BC
authors.lastname: Baumann
authors.forename: Jakob
authors.initials: J
authors.lastname: Michaëlsson
authors.forename: Hans-Gustaf
authors.initials: HG
authors.lastname: Ljunggren
authors.forename: Karl-Johan
authors.initials: KJ
authors.lastname: Malmberg
mesh_terms: D000911:Antibodies, Monoclonal / Q000378:metabolism; D003601:Cytotoxicity Tests, Immunologic; D005838:Genotype; D020544:Graft vs Leukemia Effect / Q000235:genetics / Q000276:immunology; D015234:HLA-A Antigens / Q000378:metabolism; D059870:HLA-A11 Antigen; D015791:HLA-A3 Antigen / Q000378:metabolism; D006239:Haplotypes; D006650:Histocompatibility Testing / Q000379:methods; D006720:Homozygote; D006801:Humans; D020014:K562 Cells; D007694:Killer Cells, Natural / Q000166:cytology* / Q000276:immunology* / Q000378:metabolism; D008024:Ligands; D055654:NK Cell Lectin-Like Receptor Subfamily C / Q000096:biosynthesis / Q000235:genetics / Q000276:immunology / Q000378:metabolism; D054347:Receptors, KIR3DL2 / Q000096:biosynthesis / Q000235:genetics* / Q000276:immunology / Q000378:metabolism; D033581:Stem Cell Transplantation
chemical_list: D000911:Antibodies, Monoclonal; D015234:HLA-A Antigens; D059870:HLA-A11 Antigen; D015791:HLA-A3 Antigen; C515084:KIR3DL2 protein, human; D008024:Ligands; D055654:NK Cell Lectin-Like Receptor Subfamily C; D054347:Receptors, KIR3DL2